Interpretive Summary: Southernpea varieties with the green cotyledon seed color trait are becoming popular in the southern U.S., but none of the green cotyledon varieties currently available to farmers and home gardeners are resistant to root-knot nematodes. Root-knot nematodes are prevalent in many southern soils, and these soil-borne parasites can severely reduce southernpea yields. About ten years ago, an effort was initiated at the U.S. Vegetable Laboratory in Charleston, SC, to incorporate a root-knot nematode resistance gene into the popular green cotyledon, cream-type variety Bettergreen. These efforts resulted in the August 2001 release of the variety Charleston Nemagreen. The new variety is highly resistant to root- knot nematodes. The yield potential and the plant habit, pod, seed and disease resistance characteristics of Charleston Nemagreen are quite similar to those of Bettergreen. Charleston Nemagreen is well adapted for production throughout the southern U.S., where it can be expected to produce excellent yields of cream-type southernpeas. Charleston Nemagreen is recommended for use by the frozen food industry and home gardeners.

Technical Abstract:
The USDA has released the first green-cotyledon phenotype southernpea cultivar that is resistant to root-knot nematodes (Meloidogyne spp.). The new cultivar, named Charleston Nemagreen, was developed as a replacement for Bettergreen, a popular, cream-type, green cotyledon phenotype cultivar that is quite susceptible to root-knot nematodes. Charleston Nemagreen was developed using a pedigree breeding procedure that involved a single cross between Bettergreen and US-629 and repeated single plant selections. Charleston Nemagreen originated as a bulk of an F8 population grown in 1996. The new cultivar is quite similar in plant and maturity characteristics to Bettergreen. The results of four years replicated field testing at Charleston, SC, and three years of testing in the Regional Southernpea Cooperative Trials indicate that the yield potential of Charleston Nemagreen is similar to that of Bettergreen. Charleston Nemagreen is homozygous for the Rk gene that conditions resistance to the southern root nematode (M. incognita), the Javanese root-knot nematode (M. javanica), and the northern root-knot nematode (M. hapla). Charleston Nemagreen is well adapted for production throughout the southern U.S. Charleston Nemagreen is recommended for use by the frozen food industry and home gardeners.